Semi-permanent??? blocking of a doorway

[TicklyT]

I am considering dividing the annexe at the side of my house off from the rest of the house to let as a studio appartment.

How would you recommend blocking the single doorway linking the annexe in the (originally exterior) cavity wall?

Bearing in mind I may wish to restore the doorway in the future, should I consider traditional brick / blockwork / plaster or is it possible to achieve comparable soundproof / fireproof etc. results with studwork / plasterboard and appropriate insulation?

 

[freddiemercurystwin]

You can comply with either method depending upon the existing wall thickness available, this may be child's play compared with the inevitable planning permission though .........